Sheet-engaging rolls



Nov. 22, 1960 J. D. ROBERTSON sHEET-ENGAGING ROLLS 2 Sheets-Sheet l 6 Filed Jan. 13, 1955 Nov. 2z, 1960 ,i D. ROBERTSON 2,960,753

SHEET-ENGAGING- ROLLS Filed Jan. 13, 19,55 2 Sheets-Sheet 2 INVEN TOR.

Joiz aefiso United States Patent 2,960,753 SHEET-ENGAGINGROLLS John D. Robertson, Taunton, Mass., ,assignorto ,Mount VI-Ivope Machinery Company, Taunton, Mass., a corporationof Massachusetts i :Filed Jan. Ais, 195s, seras. 481,531

1 claim. `(ci. 2st-,116)

This invention relates to improvements in sheet-en gaging rolls and methods of providing wear-surfaces thereon. More particularly, the invention provides an improved roll structure wherein the wear-surface of the -roll is `provided by a homogeneous body of wound and Vover-lapped soluble 4strip-material which is applied with -a sovlent and whose over-lapping convolutions become partially dissolved and-homogeneously merged4 in a man- .-nerl-to substantially eliminate objectionable seamsV when the solvent evaporates.

Rolls used fin the textile, paper, andV other industries "forgniding sheet materialsLand for lateral expansionjor `contraction ofrengaged ysheet materials, frequently are subjected `to surface wear to an extentwhicli may make lit desirable to be able to renew-thesurface of any par- `ticular roll. This yis particularly-true inthe case of longitudinally curved vexpander rolls-which customarilymhave aiiiexible -surface sleeve-which'-is required to rotate about lfthecurved axis of -the roll.

It is among the objects -of the present invention-to provide a'rollwhose .surface portion may `be'relatively `easily-renewed^without' the inconvenience and delay here- -tofore -involved when a rworn roll-.had to'be returned to -the manufacturer f for re-surfacing.

Another object of V` the invention is to provide a roll re-surfacing method whereby arroll may be -re-surfaced by any reasonably intelligent `personwho follows a-few simcple instructions. yA further object of the invention is to provide a roll having a surface portion-made-np ofwhelically wound YYet anotherobject of -thefinvention is to-provide a roll having a sleeve vof solubleimaterial and having soluble `stripmaterial Ihelically wound on the'isleeve with -prede- 'termined over-lapping oftheconvolutions, thersaid sleeve material and strip materialbeing subjected to thevaction of a solvent during the process of-windingthe strip mate- Arial Vthereby to attain ahomogeneous roll-surfacing body which becomes substantially -free of objectionable ridges and highly wear-resistingupon evaporationr of the solvent.

It is, moreover, my purpose and object generally to improve roll structures and methods of `renewing roll `surfaces, and especially the structures and surfacesof *longitudinally curved expander roll sand the like.

In the accompanying drawing: Fig. lis an elevational view of a longitudinallycurved Yexpander roll having a surface structure embodyingrfeatures of the invention;

Fig. 2 is an elevational view ofan end ,portionofya roll i similar -to Vthat of Fig. 1.illustrating themethodwofnre- Asurfacing the roll, portions being in medial cross-section,

2 and the scale being substantially larger Athan that of "Fig 3 is an elevational view showing opposite end portions of the roll of Fig. 1 on the s cale of Figf2;

Fig.,4 is an elevational view of a fragment at one end of the `roll of Fig. 3, showing the homogeneous nature of the applied roll surface;

Fig. 5 is a viewgenerally similar to Fig. 4 but showing a'moditied form in whichboth Vthe wound vsurfacing material andthe sleeve on which it is wound are of a nature to merge into a'homogeneous mass;

Fig. 6 is a view vgenerally similar to Fig. 2but showing a modified form of the inventionin which the edges of successive c onvolutions ofthe surfacing strip material are butted;

Fig. v7 is a fragmentary elevational view of the central portion of a `roll wound with butted edges, as inrFig.f6,

`and showing the outer layer of convolutions laid `with opposite pitch on opposite sides ofthe center of theroll; .and Y `Fig. l8 is a view generally similar to Fig. 4'but showing the-butted convolutions of the Figs. 6 and `7 embodi- Ament of the invention.

Referring to the drawings, a longitudinally curved expander roll Vis shown at 10'in Fig. l, it having acurved axle 12 which projects at each endof the roll body to facilitate mounting of the roll on avsuitablefsupportby means of clamps, or the like (not show n).

The invention `has to do with the surface structureof vrolls and a method of re-surfacing rolls, and it should lbe Vunderstood that lthe illustrated roll is lrepresentative of sheet-engaging rolls ,generally regardless of A`whether they -are straight from end to end Yor longitudinally curved.

l The illustrated roll has a series of spoolsor-'rollsecltions 14 distributed in slightly spacedrelation along the axle 12 with suitable anti-friction bearing means, as at 13 in Fig. 3, intervening between the roll sections and the axle.wherebythe roll sections 14 are freely rotatable on .the axle 12. Spacingmembers 13;a maintain the vspacing of the bearingmeans .and .roll sections in Vconjunction with endmembers 13b which are secured tothe axle 12.

VA sleeve 16 of iiexible material embraces all of the roll sections 14, tieing them together for .rotation in unison withthesleeve 16. :End caps 18, 20am-removably fixed to the adjacent endfmost roll sections 14, as at 19 in Fig.'3.

According to the invention as represented in the embodiments of Figs. 1 through 5 of .the.drawings, the surface portion of roll 10` is formed of strip material which is helically wound on sleeve 16iwith each succeeding convolution substantially over-lapping fthe preceding convolution.

Referring to'Fig. 2, the surfacing strip material 22 is` shown in the form of relatively thin Vtape having substantial width. Tape 2" wide and g thick may be V,wound on sleeve 16 with approximately 11/2l overlap of One of the end members 24 is illustrated in Fig. 2, vand also in Fig. 6, ashaving an inwardly extending annular ange 25 Yfor engaging a similar ange 15 on the adjacent end-most spool or roll section 14, with removable fastening means'25 securing the flanges 25, 15 together, so that member 24 constitutes a temporary extension of the endfmost spool orroll section 14. A sleeve elenientll.El

on member 24 constitutes a temporary extension of the roll sleeve 16 having outside diameter approximating that of sleeve 16. In the embodiments of Figs. 1-5, the first convolution of the strip material or tape 22 may be-laid directly on the sleeve element 24a of one of the members 24, as at 22 in Fig. 2, with next succeeding convolutions substantially overlapping the preceding convolution. Assuming material 2" wide with an overlap of each convolution approximating 11/2", the fourth-laid convolution will have built up the covering to four thicknesses of the tape at the lefthand 1/2" margin of the said fourth-laid convolution. Each succeeding convolution after the fourthlaid one builds up another 1/2 of covering to four thicknesses of the tape until the entire length of the roll is covered by four thicknesses of the tape. Each convolution is depressed to provide a shoulder or shoulders at the location or locations of an overlapped edge or overlapped edges of one or more previously laid convolutions, which results in a stepped form of convolutions wherein the steps approximate 1A" in width and are located at different radial distances from the roll axis. Each said step of an already laid convolution constitutes a seat for a 1/z wide portion of the next succeeding convolution, with an edge of the convolution which is being laid positioned relatively close to a said shoulder formed by the next preceding convolution. Each successive convolution extends approximately 1/2" beyond the overlapped edge of the previously laid convolution and becomes depressed over the said edge of the previously laid convolution into contact with the surface of the sleeve 16 or with an underlying portion of the previously laid convolution. Hence, the second, third and fourth convolutions all become depressed at the location of the overlapped edge of the first-laid convolution which provides an exterior relatively slight spiral shoulder 22a approximately 1/2 inward from the left-hand edge of the fourth-laid convolution 22", Fig. 2. The fifth convolution 22 is laid upon depressed portions of the fourth-laid convolution 22 with its left-hand edge closely adjacent to the said shoulder 22B. It will be apparent from Fig. 2 that the inner edges of successive convolutions occur at approximately 1/2" intervals along the surface of sleeve 16, and an outer helical shoulder 22a is provided at each so that the successive convolutions each as a portion approximately 1/2 in width at the outer surface of the tape-wound roll, and all of these surface portions of convolutions combine to produce a roll surface which is devoid of objectionable ridges or seams. The winding as shown in Fig. Z'may be continued throughout the length of sleeve 16 and onto the end member 24, at the end opposite to that seen in Fig. 2, sufficient to provide a four thicknesses coating beyond the adjacent end of sleeve 16.

The strip or tape 22 may be made of any suitably flexible and wear-resisting material, and any suitable adhesive may be provided, either on the tape or applied during the laying of convolutions for maintaining the surface covering in its helically wound condition.

After the strip or tape 22 has been wound as described in connection with Fig. 2, starting on one member 24 and ending on the other, the temporary members 24 may be removed and the portions of the surface material projecting beyond the ends of sleeve 16 may be trimmed away, after which the regular roll end caps 18, 20 may be secured in place to put the roll in readiness for service.

While various materials may be employed for the surfacing tape, such as rubber with or without fibrous reinforcement, I presently consider it preferable to employ one of the available soluble plastic materials which, in strip or tape form may be helically wound, with addition of a suitable solvent, whereby a wound roll covering, through the action of the solvent, becomes a homogeneous body. Tape 22 made of vinyl chloride may be used with satisfactory results, in which case the solvent, indicated at 23 by stippling, may be a fifty-fifty solution of methyl ethyl ketone and cyclohexanone, which may be applied to the outer surface of the tape during the process of winding the tape on a roll sleeve 16. Obviously, particular conditions to which any particular roll may be subjected in service will dictate to a considerable degree the nature of the roll-surfacing tape which will be employed.

In Fig. 2, it is not contemplated that the wound strip material or tape 22 will become strongly adhered to the roll sleeve 16, whether or not the convolutions are merged into a homogeneous mass by the action of an introduced solvent. Hence, when it becomes necessary or desirable to renew the surface of a roll as herein shown, the strip material or homogeneous mass may be cut or otherwise removed from sleeve 16 preparatory to re-surfacing of the roll. However, when a soluble tape material and solvent are employed for re-surfacing, the sleeve 16 may, if desired, be of the same material as the strip material or tape 22, or a related material, so that the solvent will act on the material of sleeve 16 as well as on the tape material thereby to render the sleeve and tape homogeneous as in Fig. 5. In such a case, evaporation of the solvent leaves a relatively hard and tough homogeneous surface mass, and any re-surfacing would need to be preceded by a grinding away of the worn coating to provide a suitable sleeve surface for reception of the re-surfacing tape windings.

Fig. 6 illustrates a modification in which the surfacing tape is helically wound in successive layers with the tape edges of the convolutions in each layer butted. The convolutions 221 of the inner layer may be laid with pitch of the convolutions in one direction and the convolutions in the second layer may be laid with pitch of the convolutions in generally opposite direction. The convolutions of the third layer may be laid the same as those of the inner layer. The butted edges are indicated at 223.

The outer layer, however, preferably has its convolutions laid with those on one side of the center of the roll pitched to the right and those on the other side of the center of the roll pitched equally to the left, as represented in Fig. 7, wherein two separate strips 222, 222 have their inner end portions tapering to a point at 2228, 222b, respectively, so that these tapered ends may be laid at the center of the roll with edges butted at 222C, and the strips wound helically from the center of the roll outwardly in opposite directions. This avoids a surface appearance which might suggest an action by the roll on sheet material tending to cause lateral travel of the sheet material in one direction or the other;

In the Figs. 6 and 7 embodiment, a solvent is applied between the convolutions of successive layers to attain a generally homogeneous surfacing mass as illustrated in Fig. 8, which is generally the same as in the Figs. 1-4 embodiment. When desired, the solvent may be introduced also between the inner layer and the member 16 on which the strip material is wound when the latter material is of a nature to be merged with the strip material as described in connection with Fig. 5.

It is intended that the patent shall cover, by suitable expression in the appended claim, whatever features of patentable novelty exist in the invention disclosed.

I claim as my invention:

A roll having a longitudinally curved axle, a sleev element of exible material extending from end to end of the roll, rotatable on said curved axle, and constituting a relatively permanent element of said roll, a relatively wide continuous strip of wear-resisting soluble material helically wound on said sleeve element from end to end thereof with each succeeding convolution over-lapping a substantial portion of the width of the next preceding convolution, each of said convolutions having a substantial portion of its width exposed at the surface of the roll and said convolutions, excepting an endmost one, each having a plurality of other substantial portions of its width disposed at different radial distances outward from the roll axis and over-lapped by portions of subsequently laid convolutions, said sleeve element having a surface portion of `soluble material compatible with the soluble material of said strip material, said over-lapped and over-lapping convolutions of soluble material and said soluble surface portion of said sleeve element being dissolved and merged into a substantially homogeneous wear-resisting surface mass extending around and from end to end of said roll.

References Cited in the file of this patent UNITED STATES PATENTS 6 Keeran Jan. 1, 1935 Atwood Oct. 8, 1935 Hemperly May 23, 1944 Dean Aug. 17, 1948 Sampson Nov. 29, 1949 Lowe Mar. 28, 1950 Stackelberg Mar. 3, 1953 Scott June 2, 1953 Winstead June 5, 1956 Dunlap .Tune 26, 1956 Gageant Nov. 27, 1956 FOREIGN PATENTS Germany July 21, 1944 

